20130929

Online reading assignment: Kirchhoff's laws (SLO campus)

Astronomy 210, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing presentations on Kirchhoff's laws.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"Learning about the Doppler effect and how it applies to objects in space was pretty cool that one can determine if an object is heading towards Earth via blueshifts, or if the object is retreating our position via redshifts."

"The continuous spectrum because it was interesting to see that the wavelengths were almost equal on a intensity versus wavelength graph."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I am having trouble determining the three different spectra when guessing at the pictures from the blog. I don't understand how we are determining the spectra from the pictures."

"How blueshifts and redshifts are detected by changes in the positions of features in a star's spectrum."

"Redshifts and blueshifts: a little confusing when you realize that the actual colors of red and blue are not seen."

Suppose you are standing on the sidewalk as a car, with its horn continuously on, passes by (video link). The loudness of the car horn:
starts high, then drops lower.  ******** [8]
starts low, then goes higher.  ** [2]
starts low, goes higher, then drops back down to low.  ********************************* [33]
starts high, goes lower, then goes back up to high.   ** [2]
(Unsure/guessing/lost/help!)  [0]

Suppose you are standing on the sidewalk as a car, with its horn continuously on, passes by (video link, same as above). The pitch (high note/low note) of the car horn:
starts high, then drops lower.  ************************ [24]
starts low, then goes higher.  [0]
starts low, goes higher, then drops back down to low.  ******** [8]
starts high, goes lower, then goes back up to high.   ******* [7]
(Unsure/guessing/lost/help!)  ** [2]

Match the spectrum type with their apperance.
(Only correct responses shown.)
Rainbow containing all colors: continuous [82%]
Rainbow with thin black lines: absorption [87%]
Colored lines on a black background: emission [82%]
Given off by hot, dense object: continuous [68%]
Given off by hot, diffuse gas atoms: emission [61%]
Passing through cool, diffuse gas atoms: absorption [61%]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can you post the answers to the flashcard questions online, so when we are studying for the quizzes we can see if we are getting the answers right?" (You can e-mail me about the questions on the archived quiz or other topics up until 10:00 PM the night before the quiz, and I will attempt to respond to you sometime later that night (or very early that morning.)

"Glad you're not that big of a Big Bang Theory fan. That show is overrated and everyone should watch Community instead!" (Word.)

Online reading assignment: work

Physics 205A, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing a presentation on work.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"I'm still kind of processing it all, but I thought it was interesting that work was a scalar without direction. I just would have thought that it would have mattered because we use direction for certain force calculations (acceleration for example)."

"I found the law of conservation of energy to be very interesting in that the total energy in the universe is unchanged by any physical process and that during a reaction the total energy before equals the total energy afterwards."

"Already knowing about physics, makes this class easier and finally taking the time to read the textbook makes everything more interesting."

"I find it interesting how there are so many different forms of energy. No one really thinks about the many forms, especially in everyday life."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I'm confused about the examples. I understand where the transfers are happening, but not how we put it into a calculation. I think I just need to see some examples in lecture."

"I had a hard time with figuring out how work could be positive, zero, or negative."

"I'm confused when calculating work when force and displacement are parallel."

"I was not confused on any of this material."

"It all seemed to make sense."

Match the amount of work exerted by these forces on an object.
(Only correct responses shown.)
Pushing along the direction of motion: positive [82%]
Pushing against the direction of motion: negative [66%]
Pushing sideways to the direction of motion: zero [64%]
Pulling such that the angle between the force and motion is an acute angle: positive [82%]
Pulling such that the angle between the force and motion is an obtuse angle: negative [66%]

State the SI unit for work, and describe how the work SI unit is related to the force SI unit.
"The unit for work is Joules, which is N × m. It is essentially how much force (N) is applied over a distance (m)."

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can I pay somebody to do this?" (*smh*.)

"Will we review trigonometry at some point?" (We already reviewed all the trigonometry you need to know.)

"The blog lectures are very visual which helps me and they are interesting."

"Can we please have lectures before reading the material at home? Can you do problems on the board? The flipped classroom is a nice idea but I think me and other classmates are finding it difficult to use." (When you (attempt to) read the textbook before you come to class, yes, I know you're confused, but by telling me in the online reading assignments specifically what you're confused on, I know which "muddiest points" I should hit on in lecture.)

"Would an opposite force applied to a moving object (kinetic friction) be negative work because it's slowing/is against the direction of motion?" (Yes. But also mathematically because the cosine of 180° (the force and the motion are opposite directions) is -1.)

20130927

Astronomy current events question: comet properties of asteroid 3552 Don Quixote

Astronomy 210L, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Northern Arizona University news release, "NAU-led Team Discovers Comet Hiding in Plain Sight," September 10, 2013
http://news.nau.edu/nau-led-teams-discovers-comet-hiding-in-plain-sight/
NASA's Spitzer Space Telescope observations of asteroid 3552 Don Quixote's __________ revealed that it is a comet.
(A) metal-poor composition.
(B) irregular orbit.
(C) faint coma and tail.
(D) core density.
(E) cratered surface.

Correct answer: (C)

Student responses
Sections 70178, 70186, 70200
(A) : 2 students
(B) : 3 students
(C) : 48 students
(D) : 4 students
(E) : 2 students

Astronomy current events question: dark matter distribution models

Astronomy 210L, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
John Jardel, Karl Gebhardt, "Texas Astronomers Unravel 20-Year Dark Matter Mystery with New Computer Models," September 10, 2013
http://mcdonaldobservatory.org/news/releases/2013/09/10
University of Texas, Austin astronomers determined the distribution of dark matter in small galaxies by:
(A) counting neutrinos in deep underground mines.
(B) observing matter and antimatter production near black holes.
(C) locating distorted star patterns behind these galaxies.
(D) running computer simulations to match observations.
(E) detecting x-rays emitted by dark matter.

Correct answer: (D)

Student responses
Sections 70178, 70186, 70200
(A) : 0 students
(B) : 10 students
(C) : 18 students
(D) : 23 students
(E) : 7 students

Astronomy current events question: Deep Impact mission ending

Astronomy 210L, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Camille Carlisle, "Deep Impact Meets Its End," September 20, 2013
http://www.skyandtelescope.com/community/skyblog/newsblog/Deep-Impact-on-the-Fritz-223311901.html
NASA's Deep Impact spacecraft is currently spinning out of control because of a:
(A) misaligned solar panel.
(B) slow radiation leak.
(C) micrometeorite collision.
(D) recent solar flare.
(E) software glitch.

Correct answer: (E)

Student responses
Sections 70178, 70186, 70200
(A) : 3 students
(B) : 1 student
(C) : 9 students
(D) : 3 students
(E) : 48 students

20130924

Online reading assignment: uniform circular motion

Physics 205A, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing a presentation on uniform circular motion.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"For uniform circular motion, the velocity vector is perpendicular to a radius drawn from the center of a circle to the position of the object, and I found that the animated *.GIF of the bowling ball and mallet clearly demonstrated that--it also shows that the speed of the bowling ball is constant, but you need to manipulate the direction of the force exerted on it to be centripetal."

That circular motion is obviously covered by Newton's second law, even when restricted to moving at constant speed along a circle."

"There was nothing interesting this time."

"That an object that is traveling in a uniform circular path will have an acceleration directed toward the center of the circular path."

"In uniform circular motion the acceleration is constant in the magnitude, but with nonuniform circular motion the acceleration changes as the speed is changing."

"That the net force for uniform circular motion must point in the inward direction. I originally assumed that it would point outwards, or that it would be in the actual direction of the circle."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I didn't really think the car arcing over the top of the hill was circular motion. I thought of it as a parabola, but I guess a parabola has a half-circle shape."

Will definitely need help applying most of this in tomorrow's class. Explanations and corrections are, in my case anyway, very necessary."

"I was having trouble identifying which direction the net force would be on the 'picto-quiz' examples."

"I don't understand how something in non-uniform circular motion can "momentarily" experience uniform circular motion."

"I do not understand how to use the net force equation for uniform circular motion."

Match the motion of an object with the applicable Newton's law.
(Only correct responses shown.)
Constant speed along a straight line: Newton's first law [95%]
Speeding up along a straight line: Newton's second law [85%]
Slowing down along a straight line: Newton's second law [89%]
Constant speed along a circular path: Newton's second law [54%]
Speeding up along a circular path: Newton's second law [93%]
Slowing down along a circular path: Newton's second law [97%]

Match the circular motion directions with their descriptions.
(Only correct responses shown.)
Along the velocity vector: tangential [51%]
In towards the center of circle: centripetal [71%]; radial [17%]
Sideways to the velocity vector: radial [34%]
Out away from the center of the circle: centrifugal [62%]
Net force on an object undergoing uniform circular motion: centripetal [44%]; radial [29%]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can you just teach the reading material in class, and we solve problems at home?" (I've seen how you do your homework in class. Believe me, you want to do your homework in class where I'm available to help you. Also, I already go over some of the reading material in class, on selected concepts you collectively are struggling with (and I do appreciate your feedback on the online reading assignments to know what these difficulties are when I plan my mini-lectures the night before class).)

"I would really like it if we could go over a few uniform versus non-uniform circular motion examples. Feeling a little shaky about this section." (As you wish. (Note: we will only consider uniform circular motion; or non-uniform circular motion that is momentarily uniform circular motion in nature.)

"Can you go over the circular motion directions?" (See the above results on this blog post. The direction labels are basic nomenclature and definitions you just need to get familiar with.)

"I would benefit greatly from the correct answers to the reading assignment survey questions. If there is a way to see them, please let me know. Thanks." (This blog. The blog that I show you at the start of every class: http://waiferx.blogspot.com.)

"How does our lab grade affect our overall grade in the class?" (From the course policy, lab is 100 points out of the total of 700 points for this course. Each whole letter grade is worth 100 points.)

20130923

Online reading assignment: runaway planets, jovian planets, and dwarf planets (oh my!) (NC campus)

Astronomy 210, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing presentations on runaway planets (Venus and Mars), jovian planets (Jupiter, Saturn, Uranus and Neptune), and the dwarf planets (and the International Astronomy Union classification scheme).

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"Majority of our greenhouse gases in our atmosphere is released by volcanoes and absorbed by oceans."

"I found the terrestrial planets interesting--the fact that venus and Earth are so alike but so different. Our size is almost the same, but yet the runaway greenhouse effect on Venus is crazy. It is interesting to me because it is a place that I can view from Earth as an evening star. Its amazing that we know so much about Venus, and yet there is still a lot to discover."

"Why Pluto is not a planet. I knew it got kicked out of the planet club, but I only knew one reason why it wasn't considered. I liked reading about both sides of this issue."

"I like how there seems to be volcanos on every planet."

"It was interesting that Jupiter's clouds look more active than Saturn's because Jupiter is more massive, so it has more convection currents. The coffee and cream analogy really helped with this concept."

"I liked the IAU classification scheme, and telling whether something was a planet, a moon, satellite, etc. It totally made sense. It was interesting because I always wondered why Pluto wasn't a planet anymore."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I think the idea of having an atmosphere is completely bizarre. I understand that it's necessary, but how does it form and how does it stay?"

"What makes a atmosphere more or less dense--for instance, the textbook said that Venus has a lot of carbon dioxide, but if there were oceans would this make the atmosphere less dense as the oceans absorb the carbon dioxide? Does gravity have anything to do with the denseness of the atmosphere?"

"I don't understand why Pluto and the other dwarf planets are in fact 'dwarf' planets. The criterion they don't meet is dominating their orbit, so why does their size play a role in identifying them?"

Which jovian planet has the coolest interior temperatures?
Jupiter (most massive).  * [1]
Saturn (most prominent rings).  [0]
Uranus (least active weather patterns).  ******** [8]
Neptune (farthest from the sun).  ************ [12]
(Unsure/guessing/lost/help!)  [0]

I believe Pluto should be a planet.
Strongly disagree.  * [1]
Disagree.  ******* [7]
Neutral.  ****** [6]
Agree.  **** [4]
Strongly Agree.  *** [3]

Briefly explain your answer to the previous question (whether Pluto should be a planet).
"When I was growing up I was taught that Pluto was a planet, it was kinda lame to hear that they unclaimed it a planet, I don't see why it took them so long to decide that. I still feel that it should be a planet."

"No, because according to the book Pluto is not large enough to dominate and gravitationally clear its orbital region of most or all other objects."

"I really don't mind whether or not Pluto is a planet."

"Why not? Mercury is a planet."

"I honestly have no opinion on Pluto. I don't know enough about astronomy to have that opinion."

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Do we ever get to see our homework scores?" (Yes, they're listed on the same pages as the quiz scores (as "R1 = Reading assignment 1," etc.).)

"I don't know if it is just me but I feel the quiz questions are way harder than what is being taught in class."

Online reading assignment: applications of Newton's laws

Physics 205A, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters on applications of Newton's laws.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"The problems for Newton's laws were a lot more conceptual than the projectile motion problems. You have to think about what forces act on each other and be very familiar with Newton's three laws."

"Friction force is interesting because it is almost always present, and when I used to play soccer, I would always consider how the grass would affect how far the ball rolled when it was thick compared to thin and short."

"That there are high points on surfaces that are invisible to our eyes, but are the cause of friction forces. The smoother the surface the less resistance."

"Honestly! If you want better traction in a rear-wheel drive car and the road, put something heavy in the trunk to increase normal force. I like real world/real situation examples."

"That when two objects are interacting with each other they have two forces working on them, which is the same force just looked at from opposite directions."

"I enjoyed learning about friction (still don't feel I have a full grasp on it). Learning about forces has really changed my perspective on terms such as weight and pull/push."

"The rules for friction were interesting. It was a challenge to do the free-body diagrams, but once I got the hang of them it was interesting to see the applications."

"That there are two different types of friction forces."

"Friction is caused by bonds between atoms that form between the 'high points' of the two surfaces that come in contact."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I think I understand Newton's laws to a certain extent, but I still am not very confident in applying them to a variety of situations."

"I just lack confidence in drawing free-body diagrams and real-world applications because it is hard for me to put the formal information into a picture."

"The differentiation between sliding friction and static friction. I don't understand how static friction can become sliding friction if the friction does not prohibit sliding."

What is the meaning of the "normal" in the "normal force?"
"In geometry, 'normal' means 'perpendicular.'"

"'Normal' in 'normal force' merely means the force pushed on from one object resting on another. Its the 'regular' force that is pressed on one object to another."

The magnitude of the static friction force on an object that is being pushed, but is still stationary:
is zero.  ***************** [17]
is a constant, non-zero value.  ********** [10]
could have any value up to a maximum amount.  ************************** [26]
(Unsure/guessing/lost/help!)  ******* [7]

The magnitude of the kinetic friction force on an object sliding at constant speed:
is zero.  **** [4]
is a constant, non-zero value.  **************************************** [40]
could have any value up to a maximum amount.  ****** [6]
(Unsure/guessing/lost/help!)  ********** [10]

The magnitude of the kinetic friction force on a sliding object that is accelerating:
is zero.  ** [2]
is a constant, non-zero value.  ********************* [21]
could have any value up to a maximum amount.  ************************ [24]
(Unsure/guessing/lost/help!)  ************* [13]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Why are we learning this?" (Because this is a physics class.)

"Can you go over a homework problem in every class if we are not getting it, and to not just say that the answer is in the back of the book. It was really helpful when you did that last class session." (If the majority of the class reports having issues with that problem, and if time allows during the brief lecture period in class. Otherwise there will be time to individually go over homework problems during the group whiteboard problem-solving period at the end of every class.)

"In class last week you tried to explain weight force versus normal force. Can you go over that again?" (Weight force is the gravitational force of Earth pulling down on an object; it always has the magnitude w = m·g. normal force is a contact force exerted by a supporting surface; its magnitude can have any value ranging from 0 (surfaces not actually touching), any positive value (where the surfaces are being pressed into each other), up to a maximum value (where the surfaces can no longer support any greater force, and would begin breaking).)

"Can we go over problems relating to applying Newton's second law? Can we please go over the word problems as a class? I'd like to spend some time going over the examples." (Yes, yes, and as time allows.)

Online reading assignment: atmosphere problems, quantum leaps, sun's outer layers (SLO campus)

Astronomy 210, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing presentations on problems caused by the atmosphere for telescope observing, quantum leaps, and the sun's outer layers.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"Twinkling is from atmospheric turbulence. "Twinkle Twinkle Little Star" has a whole new meaning. Seriously, though, I never thought that an exterior force in our atmosphere caused them to twinkle--I thought they just did on their own."

"That we really do live at the bottom of an ocean of air. That put a lot into perspective for me."

We cannot observe from Earth all of the wavelengths in the electromagnetic spectrum and so we must send out telescopes to fly out into the atmosphere. I found this interesting because I think its amazing we can observe whats being seen from these far away telescopes all the way from Earth, and we can see so far and so much with them."

"Atmospheric turbulence, because I was able to easily see what it is by imagining myself underwater looking up."

"That the jumping of 'levels' by electrons causes the emission of light."

"Light pollution--I had no clue that man-made lights and waste light from cities affected the way we see objects in the sky."

"'Neon' signs use different gasses other than hydrogen to create different colors. It is interesting because everywhere you go you see these signs hanging from windows in stores and restaurants."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I found it confusing to grasp the concept that both man-made light and/or natural light sources will be reflected by particles in the atmosphere, and wash out faint stars. It's confusing to me that both types, man-made light and natural light would have the same effect."

"Being clear on what light exactly can be collected from Earth."

"The jumping of levels by electrons. I never quite understood it in high school. In addition, I'm not sure I understand the position of the corona and chromosphere on the sun's surface."

"Why do we need to know chemistry for our class? I'm a bit scared."

"The chromosphere, corona, and photosphere were all a little bit confusing and are a little more complex than they sound."

Stars to appear to "twinkle" in the night sky because of:
"Stars appear to twinkle because when we see them from Earth's surface, we are actually viewing them through thick layers of turbulence in Earth's atmosphere."

"All the dust and light in the sky."

A large modern optical telescope in outer space would have images with better __________ than a comparable ground-based telescope.
brightness.   *********** [11]
resolution.  ************* [13]
magnification.   [0]
(None of the above choices.)  [0]
(Two of the above choices.)  ********** [10]
(All of the above choices.)  ********** [10]
(Unsure/guessing/lost/help!)  [0]

An electron in an atom must emit a photon when it jumps from a __________ energy orbital to a __________ energy orbital.
lower; higher.  ********* [9]
higher; lower.  ********************************** [34]
(Both of the above choices.)  [0]
(Unsure/guessing/lost/help!)  * [1]

An electron in an atom must absorb a photon when it jumps from a __________ energy orbital to a __________ energy orbital.
lower; higher.  ********************************** [34]
higher; lower.  ********* [9]
(Both of the above choices.)  [0]
(Unsure/guessing/lost/help!)  * [1]

The exterior of the sun, from inner to outermost layers, are the:
(Only correct responses shown.)
inner: photosphere [68%]
middle: chromosphere [77%]
outer: corona [64%]

State your preference regarding miso soup.
Strongly dislike.  [0]
Dislike.  * [1]
Neutral.  ********* [10]
Like  *********** [11]
Strongly like.  **************** [16]
(I don't know what miso soup is.)  ****** [6]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"I found it difficult to relate the astronomers to their individual models and theories, it wasn't necessarily confusing, it just took time and the flashcard questions to help."

"The quizzes you have posted from the past semester and the flashcard question packets were helpful study guides for quizzes!"

"Should we start preparing for the midterm?" (Survive the quiz first. But by studying for the quiz, in a way you are studying for the midterm.)

"Did you see that full moon the other night? Did that have anything to do with the huge waves at Morro Bay?" (Yes (that was the closest full moon to the fall equinox, making it the Harvest Moon), and yes (as full and new moons are associated with maximum tides).)

"When will we get the opportunity to go to an observatory?" (We just did last class, to measure the parameters of the telescope. Weather permitting, we'll do it again in a future class, and look at the sun through the telescope.)

"Please help with understanding the different types of radio waves. Also, how do they separate the different waves when they are unable to be seen?" (They're separated by frequency on a radio receiver--corresponding to the numbers on your dial (or digital display).)

"I think that I'm going to have to get some miso soup for lunch thanks to this homework assignment." (Mission accomplished.)

"What is a granule?" (Here, have some miso soup.)

"I'm surprised that orange-red is the only color produced by neon yet, a lot of neon signs are multi-colored." (Those other colored signs don't contain neon, but other types of atoms that give off other types of photons.)

20130920

Astronomy current events question: NASA LADEE mission

Astronomy 210L, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
NASA's Ames Research Center New Media Innovation Team, "NASA LADEE Mission Infographic--Long Scroll Version," September 9, 2013
http://www.nasa.gov/mission_pages/ladee/infographic/
NASA recently launched the Lunar Atmosphere and Dust Environment Explorer (LADEE), which will study the moon's atmosphere by:
(A) revisiting an earlier Apollo mission landing site.
(B) crashing into the moon's north pole.
(C) making low orbits around the moon.
(D) scooping up and returning samples to Earth.
(E) measuring its magnetic fields.

Correct answer: (C)

Student responses
Sections 70178, 70186, 70200
(A) : 2 students
(B) : 0 students
(C) : 43 students
(D) : 10 students
(E) : 5 students

Astronomy current events question: Phobos annular solar eclipse

Astronomy 210L, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
Guy Webster, "NASA Mars Rover Views Eclipse of the Sun by Phobos," August 28, 2013
http://www.jpl.nasa.gov/news/news.php?release=2013-263
NASA's Mars rover Curiosity observed an annular eclipse of the sun by Mars' moon, Phobos, which is:
(A) on a collision course with Mars' other moon, Deimos.
(B) an indication of a hollow core.
(C) viewable now because of solar flares.
(D) about to burn up in Mars' atmosphere.
(E) too small to completely cover the sun.

Correct answer: (E)

Student responses
Sections 70178, 70186, 70200
(A) : 1 student
(B) : 0 students
(C) : 2 students
(D) : 2 students
(E) : 55 students

Astronomy current events question: exoplanet GJ1214b water-rich atmosphere?

Astronomy 210L, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students are assigned to read online articles on current astronomy events, and take a short current events quiz during the first 10 minutes of lab. (This motivates students to show up promptly to lab, as the time cut-off for the quiz is strictly enforced!)
SciTechDaily staff, "Observations Indicate Super-Earth GJ 1214 b Has a Water-Rich Atmosphere," September 4, 2013
http://scitechdaily.com/observations-indicate-super-earth-gj-1214-b-water-rich-atmosphere/
Subaru Telescope observations of __________ indicate exoplanet GJ 1214 b may have a water-rich atmosphere.
(A) scattered light.
(B) glowing clouds.
(C) Doppler blue-shifts.
(D) glacier ice.
(E) chlorophyll compounds.

Correct answer: (A)

Student responses
Sections 70178, 70186, 70200
(A) : 25 students
(B) : 6 students
(C) : 20 students
(D) : 7 students
(E) : 1 student

20130917

Online reading assignment: Newton's third law

Physics 205A, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing a presentation on Newton's third law.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"That two objects exhibit forces on each other of equal magnitude--I would have thought the larger object would have a greater magnitude force."

"The elevator questions were interesting. I had someone explain it in a different way which helped me to understand it. Imagine driving a car and you accelerate. Are you putting more weight against the seat? What about when you break or move at a constant rate. This helped me visualize it much better."

"Newton's third law does not involve velocity, even though it's a law about motion."

"All motion can be categorized into velocity that is constant and unchanging, or velocity is changing."

"Forces are between two objects, because I would think that one object can exert force without another object."

"The three-part POF-OST-ITO checklist, because I feel like this will really help me keep everything straight when I am confused on a problem."

"If one of the three-part POF-OST-ITO checklist does not work then Newton's third law does not apply."

"Two objects can have the same magnitude of force, but the effect can be different based on each object's mass."

"There must two objects exerting forces or there will not be an interaction at all."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"Not quite sure how this converts to equation form. Would appreciate it if we could cover a few practice problems concerning this subject tomorrow."

"I understood it pretty well."

"Not sure what is meant mean by internal or external systems."

Consider two categories of motion: (1) Velocity that is constant and unchanging. (2) Velocity that is changing. Discuss whether or not there would be a third category of motion not already covered under these two categories.
"There is no third category. These two categories summarize all types of motion."

"The only thing I can think of is a velocity that is zero and unchanging. But this may be under the first category (1) that is listed."

"There are two factors of motion and two factors of force. Motion: constant or changing. Force: zero or non-zero."

"Constantly changing velocity? Is that the same as the second category (2)?"

"Motion in which the velocity starts and stops during the interval?"

An "interaction pair" (or "interaction partners") refers to a pair of:
objects.  ********** [10]
forces.  ******************************** [32]
(Both of the above choices.)  ********** [10]
(Unsure/guessing/lost/help!)  **** [4]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can you please explain the equations related to Newton's third law?" (Strictly speaking, there are no equations associated with Newton's third law. Newton's third law is a statement of a fundamental property of forces. A really important fundamental property.)

"I love mnemonics, so having the POF-OST-ITO checklist is a huge help!" (Me, too. I have CRS.)

"Can we discuss what people were doing wrong or not understanding from Quiz 2?" (This is what the blog posts are for.)

"I need help." (I want to help you. Let's make this happen.)

"Your phone is awesome!" (Apparently awesome can unexpectedly fail. That's what a phone exchange warranty is for.)

Physics quiz question: Penguin B UAV catapult time

Physics 205A Quiz 2, fall semester 2013
Cuesta College, San Luis Obispo, CA

"6 kJ Portable Pneumatic Catapult"
UAV Factory
uavfactory.com/product/21

A portable pneumatic catapult[*] is able to launch a Penguin B unmanned aerial vehicle (UAV) from rest to a final speed of 23 m/s along a 4.0 m rail. Assume that the rail is horizontal, and that acceleration of the UAV starting from rest to when it is launched is constant. The elapsed time for the UAV be catapulted from rest to its final speed is:
(A) 0.35 s.
(B) 0.60 s.
(C) 0.90 s.
(D) 2.9 s.

[*] UAV Factory, "6 kJ Portable Pneumatic Catapult," uavfactory.com/product/21.

Correct answer (highlight to unhide): (A)

The following quantities are given (or assumed to be known):

(x0 = 0 m),
x = +4.0 m,
v0x = 0 m/s,
vx = +23 m/s.

So in the equations for constant (average) acceleration motion in the horizontal direction, the following quantities are unknown, or are to be explicitly solved for:

vx = v0x + ax·t,

x = (1/2)·(vx + v0xt,

x = v0x·t + (1/2)·ax·(t)2,

vx2 = v0x2 + 2·ax·x.

With the unknown quantity t to be solved for appearing in the second equation, with all other quantities given (or assumed to be known), then:

x = (1/2)·(vx + v0xt,

t = 2·x/(vxv0x) = 2·(+4.0 m)/(+23 m/s − 0 m/s) = 0.347826087 s,

or to two significant figures, t = 0.35 s.

(Response (B) is sqrt(vx)/(2·x); response (C) is t = sqrt(2·x/(9.80 m/s2)); response (D) is vx/(2·x).)

Sections 70854, 70855, 73320
Exam code: quiz02p3nG
(A) : 55 students
(B) : 7 students
(C) : 2 students
(D) : 4 students

Success level: 80%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.54

Physics quiz question: fastest speed on vx(t) graph

Physics 205A Quiz 2, fall semester 2013
Cuesta College, San Luis Obispo, CA

The vx(t) graph of an object 
traveling along a straight line is shown at right. The object starts at x = 0 at t = 0. When did the object experience its greatest 
speed?
(A) 2 s < t < 3 s.
(B) t = 3 s.
(C) 3 s < t < 6 s.
(D) (More than one of the above choices.)

Correct answer (highlight to unhide): (B)

The object is moving in the +x direction, where it speeds up from 0 m/s to +1 m/s from 2 s < t < 3 s; and slows down from +1 m/s to 0 m/s from 3 s < t < 6 s. Thus the object has its greatest speed at t = 3 s. (The slope of this vx(t) graph is the acceleration ax of the object, which is + 1 m/s2 from 2 s < t < 3 s; and ax = -0.3 m/s2 from 3 s < t < 6 s.)

Sections 70854, 70855, 73320
Exam code: quiz02p3nG
(A) : 34 students
(B) : 32 students
(C) : 3 students
(D) : 0 students

Success level: 46%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.68

Physics quiz question: S.M.T.H. record toss

Physics 205A Quiz 2, fall semester 2013
Cuesta College, San Luis Obispo, CA

"S.M.T.H. (Send Me To Heaven)" (excerpt)
petrsvar
youtu.be/pXr84w1cWIU

S.M.T.H. (Send Me To Heaven) is an Android application that registers how high a device is thrown up in the air.[*] The world record holder[**] was a device thrown up to a maximum height of 44.19 m from where it was released. Neglect air resistance. Choose up to be the +y direction. This device was released with an initial upwards velocity of:
(A) +1.36 m/s.
(B) +3.00 m/s.
(C) +9.02 m/s.
(D) +29.4 m/s.

[*] play.google.com/store/apps/details?id=com.carrotpop.www.smth.
[**] "World Top 10: 1. LIATO, 44.19 m," as of August 8, 2013.

Correct answer (highlight to unhide): (D)

The following quantities are given (or assumed to be known):

(t0 = 0 s),
(y0 = 0 m),
y = +44.19 m (at maximum height above where it was released),
vy = 0 m/s (at maximum height above where it was released),
ay = –9.80 m/s2.

So in the equations for constant acceleration motion in the vertical direction, the following quantities are unknown, or are to be explicitly solved for:

vy = v0y + ay·t,

y = (1/2)·(vy + v0yt,

y = v0y·t + (1/2)·ay·(t)2,

vy2 = v0y2 + 2·ay·y.

With the unknown quantity v0y to be solved for appearing in the fourth equation, with all other quantities given (or assumed to be known), then:

vy2 = v0y2 + 2·ay·y,

v0y2 = vy2 – 2·ay·y = (0 m/s)2 – 2·(–9.80 m/s2)·(+44.19 m) = 866.124 m2/s2,

v0y = ±29.42998471 m/s,

or to three significant figures, the initial upwards velocity (choosing the positive root) is +29.4 m/s.

Response (A) is 2·sqrt(y)/ay; response (B) is t = sqrt(2·y/ay); response (C) is 2·y/ay.

Sections 70854, 70855, 73320
Exam code: quiz02p3nG
(A) : 2 students
(B) : 5 students
(C) : 9 students
(D) : 53 students

Success level: 77%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.46

Physics quiz archive: kinematics, free fall

Physics 205A Quiz 2, fall semester 2013
Cuesta College, San Luis Obispo, CA
Sections 70854, 70855, 73320, version 1
Exam code: quiz02p3nG


Sections 70854, 70855, 73320 results
0- 6 : * [low = 6]
7-12 : *********
13-18 : *********************
19-24 : ************************ [mean = 20.0 +/- 5.9]
25-30 : ************** [high = 30]

Online reading assignment: atmosphere problems, Earth, the moon, Mercury (NC campus)

Astronomy 210, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing presentations on problems caused by the atmosphere for telescope observing, Earth, and the impacted worlds: the moon, and Mercury.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"The comparison of atmospheric turbulence and looking through ripples in water was really interesting. I never would've thought of it that way."

"The aircraft that was turned into a telescope...how cool is that?"

"Infrared, ultraviolet, x-ray, and gamma ray light from space are all absorbed in Earth's atmosphere, never reaching the surface."

"I was surprised to see that Mercury had a much bigger core compared to the moon; the moon is nearly all crust, and Mercury is nearly all core. I wonder why that is."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"What evidence supports Mercury being formed by two colliding bodies?"

"I'm still confused about telescopes."

"The questions about what is younger on the surfaces of the moon or Mercury, not really understanding those."

"The large-impact hypothesis of the moon's formation."

"I didn't know what a Cornish hen was."

"The different types of electromagnetic radiation (ultraviolet, x-rays, gamma rays). This section was like reading a foreign language. It would help if you had time in class to quickly go over the differences and what scientists use them for."

Stars to appear to "twinkle" in the night sky because of:
"Stars appear to twinkle in the night sky because we see them from Earth's surface through thick layers of moving air in the atmosphere. The light from the star is bent and goes in many different directions. The refractions, when seen with the naked eye, gives you the appearance of twinkling."

"The amount of atmosphere between you and the star."

"Stars appear to twinkle due to the light pollution from urban areas and pollution in general and the lens of the telescope catching this."

A large modern optical telescope in outer space would have images with better __________ than a comparable ground-based telescope.
brightness.   * [1]
resolution.  ************* [13]
magnification.   [0]
(None of the above choices.)  * [1]
(Two of the above choices.)  ****** [6]
(All of the above choices.)  ******* [7]
(Unsure/guessing/lost/help!)  ** [2]

__________ produced the carbon dioxide in Earth's atmosphere.
Volcanoes.  ****************** [18]
Oceans.  ****** [6]
Plants.  * [1]
The greenhouse effect.  ***** [5]
(Unsure/guessing/lost/help!)  [0]

__________ prevent(s) Earth's atmosphere from building up too much carbon dioxide.
Volcanoes.  [0]
Oceans.  ******************* [19]
Plants.  **** [4]
The greenhouse effect.  ******* [7]
(Unsure/guessing/lost/help!)  [0]

Which feature on the moon is the youngest?
Craters partially filled in with flat lava plains.  ***** [5]
Craters on top of flat lava plains.  *********** [11]
Flat lava plains.  ******* [7]
(There is a tie.)  ** [2]
(Unsure/lost/guessing/help!)  ***** [5]

Which feature on Mercury is the youngest?
Lava-filled lowlands.  ******* [8]
Large crater basins.  ******* [8]
Long curving ridges.  **** [4]
(There is a tie.)  **** [4]
(Unsure/lost/guessing/help!)  ****** [6]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"It appears smaller terrestrial bodies just don't have what it takes to support life; they're smaller mass means faster cooling, thus less volcanic activity, a thinner atmosphere, a lesser greenhouse effect, and less of a chance to develop complex life. Assuming similar composition, roughly 1 AU distance and a similar main-sequence star, what might we generally assume about these super-earths? Inhospitable hot houses like Venus?" (Yes, possibly too hot to support life (as we know it).)

"How many star parties have you been to while teaching astronomy?" (A lot.)

"Well, without people actually on the moon to study the moon all the time, how can we tell what is new and what is old? I mean, who's to say that this crater is newer than that crater? What if two craters have been there long before the invention of the telescope, how would we know which one is older than the other? It's confusing!" (Going to the moon and bringing back samples from various locations was exactly the evidence needed to answer this question.)

"This is such an interesting class. I love that I learn something new every day. I always find myself telling friends what I learned too!"

20130916

Online reading assignment: history of astronomy, telescope powers (SLO campus)

Astronomy 210, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing presentations on reviewing the history of astronomy, Kepler's and Newton's laws, and telescope powers.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"The ice-skater effect really interesting. With this visual, I can more easily see where the arms (planets) move slowest when farthest from the body (sun) and move fastest when brought nearest to the sun."

"Magnifying power is the least important power of a telescope. It seems like that would be really important, but nope, not as important as light-gathering power and resolving power."

"Closed orbits versus open orbits--if an object has a high enough velocity, then it would be able to leave its closed orbit and enter an open orbit."

"The first models of our universe and solar system were interesting, and I was thinking about how much they knew even though a lot of it was wrong, but did all that work with no technology."

"Learning about Kepler's laws and Newton's laws. They set a standard for science and discovering how planets move, and it was personally interesting to read the difference between the two scientists."

"Why planets move--because they are forced to orbit the sun because of the sun's gravitational force."

"I like how Tycho Brahe wore fake noses. I don't know why I just find it kind of funny."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"It is difficult to grasp the concept that a planet in an inner orbit takes less time to complete an orbit, while a planet in an outer orbit takes more time to complete an orbit."

"The telescopes were way more complex than I thought. I think I'll understand more when I get to really look at it in person."

"What fprimary and feyepiece are, and why measuring them is important."

"The direction of a planet in retrograde motion and in prograde motion."

"The telescopes parameters and powers were confusing--I needed more explanation to go with all of the photos in the presentation."

"How retrograde motion works to reverse a planet's movement."

When a planet is undergoing retrograde motion, over several nights it moves __________ with respect to the background stars.
east to west.   **************** [16]
west to east.  ************** [14]
(Either of the above choices is possible.)   ******** [8]
(Unsure/lost/guessing/help!)  ** [2]

When a planet is undergoing prograde motion, over several nights it moves __________ with respect to the background stars.
east to west.   ****************** [18]
west to east.  ******************** [20]
(Either of the above choices is possible.)   [0]
(Unsure/lost/guessing/help!)  ** [2]

The __________ powers of a telescope depends on the: (Only correct responses shown.)
light-gathering power: diameter of the primary lens/mirror [70%]
resolving power: diameter of the primary lens/mirror [45%]
magnifying power: both the focal lengths of the primary lens/mirror and eyepiece: [33%]

The least important feature to consider when purchasing an optical telescope is the __________ of its images.
brightness   * [1]
resolution.  * [1]
magnification   *********************************** [35]
(Two of the above choices.)  [0]
(Unsure/lost/guessing/help!)  *** [3]

Briefly explain your answer for the least important feature to consider when purchasing an optical telescope.
"If you can't gather enough light to see something, or have it clear enough, it won't matter if it's big! That's why I chose magnification as the least important feature to consider."

"Considering the ultimate goal of viewing the stars/planets, the resolution is not the first priority."

"I could not find nor formulate an answer for the question."

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can a lunar eclipse occur during the very next full moon after a solar eclipse (or vice versa)?" (Yes, provided that the moon's orbit is still sufficiently aligned edge-on with the sun in the two weeks between the eclipses.)

"So all you need to make a telescope is some mirrors or a lens and a giant tube?" (Essentially, yes.)

"Approximately how much money is that huge Thirty-Meter Telescope in Hawaii going to cost?" (About $970 million to $1.2 billion.)

"I am confused on how checking your grade works on the site. I could see it, but it didn't make sense." (We'll go over that in class.)

Online reading assignment: forces and motion

Physics 205A, fall semester 2013
Cuesta College, San Luis Obispo, CA

Students have a weekly online reading assignment (hosted by SurveyMonkey.com), where they answer questions based on reading their textbook, material covered in previous lectures, opinion questions, and/or asking (anonymous) questions or making (anonymous) comments. Full credit is given for completing the online reading assignment before next week's lecture, regardless if whether their answers are correct/incorrect. Selected results/questions/comments are addressed by the instructor at the start of the following lecture.

The following questions were asked on reading textbook chapters and previewing a presentation on forces and motion.

Selected/edited responses are given below.

Describe something you found interesting from the assigned textbook reading or presentation preview, and explain why this was personally interesting for you.
"There is a difference between mass and weight. I believed that they were the same thing but after reading the books example of a shuffleboard puck it makes perfect sense as to why they are different."

"When speed and direction are constant the sum of the forces is zero."

"I did not know that forces could 'cancel' each other out."

"Net force."

"The motion flowchart, because it points out exactly which newton law is needed."

Describe something you found confusing from the assigned textbook reading or presentation preview, and explain why this was personally confusing for you.
"I am incredibly confused about inertia! I need visuals and examples. The book throws out a bunch of definitions and I became increasingly confused."

"I'm still not 100% when Newton's first law is applied and when his second law is applied. I understand that Newton's first law needs constant speed but I still don't quite grasp the idea of it all."

"The motion flowchart and the subsequent slides of the presentation were confusing because Newton's first and second laws were not defined before going through all of the slides."

I wasn't sure which category of Newton's law the landing F-35B was in."

"I think that this section was straightforward for me."

"I am confused with the concept of net force. I understand when and what equation to use depending on the net force but I don't understand when forces acting on an object will create a zero net force. Must they always be opposite and equal magnitude?"

"Vector forces."

"Deciding if the net force is zero or not."

There could be as few as __________ (non-zero) force(s) acting on an object, such that the net force would be zero.
one.  ************** [14]
two.  ************************* [25]
three (or more).  ***** [5]
(Unsure/guessing/lost/help!)  ************ [12]

For all cases of a moving object with zero net force exerted on it, its speed must be:
decreasing.  ** [2]
constant.  ********************************************* [45]
increasing.  [0]
(More than one of the above choices.)  ***** [5]
(Unsure/guessing/lost/help!)  **** [4]

Ask the instructor an anonymous question, or make a comment. Selected questions/comments may be discussed in class.
"Can we please go over the shoveling snow example from the book and relating it to inertia?" (The non-sticky dry snow coming off of a shovel is like Mini-Me in this clip. No forces exerted, then no change in motion.)

"Why is the acceleration of an object proportional to the net force acting on it?" (This is always observed to happen. So let's turn it around, from instead of asking why this is always observed, to saying that it mustbe a law that is always obeyed!)

"What if only one force acts on an object? I'm unsure if it it could be Newton's first law, because how does it cancel out?" (If only one force acts on an object with no other forces available to cancel it out, then the net force is non-zero, making this a Newton's second law case.)

"The whiteboard lecture notes posted on Twitter were really helpful to study for the quiz."

"Twitter? What is Twitter? How does Twitter work?" (As noted in the syllabus, search for the hashtag: #CuestaPhys205A for course-related announcements.)

20130915

Astronomy quiz question: Camelopardalis from lowest to highest position in sky

Astronomy 210 Quiz 1, fall semester 2013
Cuesta College, San Luis Obispo, CA
The diagram at right shows positions of constellations and stars near the horizon, as seen at 9:00 PM by an observer in 
San Luis Obispo, CA. Ignore daylight saving 
time. Assume you can see stars in daylight. How many hours will pass 
until the constellation Camelopardalis 
reaches its highest point in the sky?
(A) 1 hour.
(B) 6 hours.
(C) 12 hours.
(D) 24 hours.

Correct answer (highlight to unhide): (C)

Using a starwheel (planisphere), the sky as shown is 9:00 PM on July 20 (or some other start time/date can be selected). Camelopardalis will be above Polaris at 9:00 AM on the next day, July 21, approximately 12 hours later.

Section 70158
Exam code: quiz01n9YE
(A) : 1 student
(B) : 7 students
(C) : 22 students
(D) : 1 student

Success level: 73% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.51

Astronomy quiz question: Arcturus setting versus Spica setting

Astronomy 210 Quiz 1, fall semester 2013
Cuesta College, San Luis Obispo, CA
The diagram at right shows positions of constellations and stars near the horizon, as seen at 8:00 PM by an observer in San Luis Obispo, CA. Ignore daylight saving time. 
Assume you can see stars in daylight. Which star will set first?
(A) Arcturus.
(B) Spica.
(C) (There is a tie.)
(D) (Neither star will set, as they are circumpolar.)

Correct answer (highlight to unhide): (B)

Using a starwheel (planisphere), the sky as shown is 8:00 PM on April 10 (or some other start time/date can be selected). Spica will set first at 5:30 AM the next day (April 11), while Boötes will set later at 8:30 AM.

Section 70158
Exam code: quiz01S0u7
(A) : 4 students
(B) : 37 students
(C) : 2 students
(D) : 3 students

Success level: 80% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.42

Astronomy quiz question: moonrise to moonset time

Astronomy 210 Quiz 1, fall semester 2013
Cuesta College, San Luis Obispo, CA

Approximately how much time elapses between moonrise and moonset?
(A) An hour.
(B) Several hours.
(C) 12 hours.
(D) 24 hours.
(E) Several days.
(F) One week.
(G) Several weeks.
(H) 28 days.

Correct answer (highlight to unhide): (C)

Earth's rotation causes the moon to rise and to set, and assuming that the moon's revolution around Earth is a much slower rate (a month-long period) compared to Earth's rotation (24-hour period), then the moon will take approximately 12 hours from rise to set.

Section 70160
Exam code: quiz01n9YE
(A) : 0 students
(B) : 0 students
(C) : 26 students
(D) : 2 students
(E) : 0 students
(F) : 0 students
(G) : 0 students
(H): 1 student

Success level: 84% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.38

Astronomy quiz question: time to change moon phases

Astronomy 210 Quiz 1, fall semester 2013
Cuesta College, San Luis Obispo, CA

Approximately how much time elapses between first quarter to third quarter?
(A) An hour.
(B) Several hours.
(C) 12 hours.
(D) 24 hours.
(E) Several days.
(F) One week.
(G) Several weeks.
(H) 28 days.

Correct answer: (G)

The moon will take approximately four weeks to go through all eight of its phases, such that it will take approximately two weeks to go through four phases (starting from first quarter, to go through waxing gibbous, full moon, waning gibbous, to end at third quarter).

Section 70158
Exam code: quiz01S0u7
(A) : 0 students
(B) : 0 students
(C) : 2 students
(D) : 0 students
(E) : 1 student
(F) : 8 students
(G) : 34 students
(H) : 1 student

Success level: 74% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50

Astronomy quiz question: moon phase high overhead at sunrise

Astronomy 210 Quiz 1, fall semester 2013
Cuesta College, San Luis Obispo, CA

Which phase will the moon have when it is overhead at 6:00 AM? Clearly circle your answer below.

Correct answer: (B) (Third quarter moon).

Note that response (F) (first quarter) is the phase that the moon would be in if it is highest overhead at 6:00 PM (noon).

Section 70158
Exam code: quiz01S0u7
(A) : 0 students
(B) : 26 students
(C) : 2 students
(D) : 1 student
(E) : 2 students
(F) : 7 students
(G) : 3 students
(H) : 2 students
(No responses): 2 students

Success level: 57% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.50